drm/panthor: Reset queue slots if termination fails

drm/panthor: Reset queue slots if termination fails

Make sure the queue slot is reset even if we failed termination so
we don't have garbage in the CS input interface after a reset. In
practice that's not a problem because we zero out all RW sections when
a hangs occurs, but it's safer to reset things manually, in case we
decide to not conditionally reload RW sections based on the type of
hang.

v4:
- Split the changes in two separate patches

v5:
- No changes

v6:
- Adjust the explanation in the commit message
- Drop the Fixes tag
- Put after the timeout changes and make the two patches independent
  so one can be backported, and the other not

v7:
- Use the local group variable instead of dereferencing csg_slot->group
- Add Steve's R-b

v8:
- No changes

Signed-off-by: Ashley Smith <ashley.smith@collabora.com>
Reviewed-by: Steven Price <steven.price@arm.com>
Link: https://patch.msgid.link/20251113105734.1520338-3-boris.brezillon@collabora.com
Signed-off-by: Boris Brezillon <boris.brezillon@collabora.com>